PCB Corrosion?

Last weekend I aquired an Apple Lisa 2/5 (finally!!), however the NiCad batteries that backed up the system clock have corroded and leaked all over the IO board and the backplane/motherboard (system uses a nifty CPU-on-card design like the OLD computers). Does anyone have any magic solutions to removing the green gunk from the printed circuit boards and components? I'm wanting to remove the stuff and preserve the system from further corrosion. (and yes, I am taking out those damn things) The green gunk has messed up one of the card slots so the IO card doesn't go. I plan to clean that out using one of those Nintendo cartridge slot cleaners (little card/pad thingy that you put stuff on and insert into slot). That'll get her running again for a while... but I really need all the gunk off and the corrosion STOPPED. any ideas that help save my Lisa would be greatly appreciated! chris starling